This invention relates to linear bearing for use in supporting a heavy load between two mechanical component parts and to facilitate relative linear sliding movement between such component parts.
In transporting a load over a linear distance, such as in a conveyor belt system, the load is normally disposed on a loading platform which is supported on guiding rails. Bearings are provided between the loading platform and the guiding rails to enable the platform to move smoothly over the latter. Heretofore, round bearing balls are commonly employed for the purpose. The platform is mounted to the bearing body. A plurality of round bearing balls are provided in the bearing assembly to support the load as well as to facilitate the relative sliding movement of the platform to the supporting rails. Although the bearings with round bearing balls provide generally acceptable support, they are complex in construction and are difficult to fabricate particularly due to the difficulty in placing and maintaining round bearing balls in position during assembly of the bearing. A four-way loaded type linear bearing is shown in U.S. Pat. No. 4,253,709 by H. Teramachi. In such improved linear bearing the load is supported by a plurality of round bearing balls arranged in four rows which provide a balanced support for the load as well as provide a smooth sliding means for moving the support relative to the rail. However, the linear bearing shown therein is still very complex in construction, and difficult to fabricate since it is cumbersome in installing the round bearing balls into the bearing body and it is difficult to provide accurately circular channels in the bearing body for housing the round bearing balls. For this reason, the bearing balls tend to make only a point contact or several point contacts with the channel wall rather than fully supported thereby. Moreover, the round bearing balls make only a single point contact with the rail surface, thus creating a concentration of force on a single point on the bearing balls resulting in inherent accelerated wear in the round bearing balls and the breakdown of the bearing on the whole.
Furthermore, the complex construction of such known linear bearing renders it very difficult to disassemble the same for repair and maintenance purposes.